Hydraulic draft controller



Oct. 18,1927.

W. L. MORE}? HYDRAULIC DRAFT CONTROLLER Filed Au. 5. 1925 ATTORNEY.

Patented 0a. 18} 1927.

UNITED STATES WILLIAM L. MORRIS, OF OAK PARK, ILLINOIS.

HYDRAULIC DRAFT CONTROLLER."

Application filed-August 5, 1925'. Serial'No. 48,219.

This invention relates primarily to a thermost-at placed in the smoke flue which operates'a water valve-of a hydraulic ram, utilizing the small travel-and power of the thermostat to. handle the small 'valves, which admit water' of sufficient quantity and pressure to handle the draft controlling device with ample reserve power -to insure dependability. Other objects of the invention will appear hereinafter;

In the accompanying drawing, Fig. 1 shows in section the hydraulic controller as attached to the smoke flue, with thermostat, dam-per and check, also the lower portion offuel burner and waste waterconnections and the connection to the different controls; and Figs. 2, 3, 4, 5 show the starting and finishing positions of the pull chains operating levers for the three draft controls.

In carrying out this invention, the quantity of water used is very small and would be a ne ligible expense if wasted, but where humidi ers are used, they should be constantly supplied with a similarly small quantity and this controller serves as a constant means of supplying this water without theuncertainties arising in use of needle valve control. There are three means of controlling draft; ,by regulating the amount of air that passes through the grates which is commonly termed the draft control; by regulating the freedom that gases may discharge from the furnace which is known as damper control; and the regulation of the intensity of draft, by-means of the check which admits air direct to the smoke flue.

The usual method of control is to set the damper so it will prevent waste of fuel as would bethe case of too strong draft when the other controls are set for full draft; the regulating is done b opening more or less either thedraft or t e check while the other control. is closed. This system is that ordinarily employed both for automatic or hand control and is wasteful, slow in responding to higher heat demands and causes smoke to discharge from" fire door opening when the door is opened, due to thechilling of the smoke flue and chimney by having the check open whichreduces the draft intensity. The check is essential only for. extreme conditions such as burning a bi charge of loose, highly combustible niateria but for the ordinary, regular conditions,

the check should not be in operation as a control, the control being by damper and draft, the draft being entirely closed before the damper even starts to close.

The'system here shown and described complies-with the demands for highest efi ioiency. o0

full op en,-'-a complete-cycle of controller movement starting ,frornfull shut ofi high heat position is asffollows; as heat in flue drops through the first A; of itscontrolling range, it closes the check gradually and in accordance ,with the temperature drops until the check is closed, then u n reaching the. second 4, of thecontro ing range, the damper starts to open'and continues to open until the temperature has dropped its range and damper is full 0 en and as the temperature starts to drop 1n its third of the controlling range, the draft starts to open and continues to open until the full temperature range is reached and then the draft is full open; as heat in the flue rises 30 and passes by. the low point of temperature range (which.'-m'ay be, say 150 degrees F.) then the draft" startsto close and is closed at the beginning of the second of ran e when the damper starts to close andis ful y closed at end of this second A; of range when the check starts to open and is fully open when the high point of the range is reached.

' The draft-Ilis'always entirely shut whenever the damper is closed or partially closed and-wheneverthe check is more or less open. This is essential to avoid escape of gases.

Every small change in temperature of line gases causes a corresponding small change 1n the draft control. There are two distinctly waste water discharges carried to the humidifiers or ash pit, the one from the hydraulic motor which discharges under some pressure, enough to back up in the leak- 10oage drain and overflow, also a separate drip line to carry off the gravity flow leakage drips.

Referring now more particularly to the drawing, a" smoke flue 1 connects the fuel burner with the .chimney; the ash pit of furnace is shown at 2 with grates 3, a fire pot 4, a fire door 5, an ash door 6, a draft control door 7, an humidifier 8 with an overflow 9', and drip-connection 10 to the ash 11-0 pg; 2. A/damper 11 oscillates approximately degrees together with its axis shaft '12 and its operating lever 13 which has a crank pin 14. A check door 15 is hinged at 16 to its frame 17 with lever arm 18. The thermostat has two iron expansion members 20 and two brass expansion members 21 secured in pairs with rivets 22. The inner end of the thermostat is supported by extension 23 in a hole in flue 1. The flue 1 has an opening communicating with a flue exstension box 25 having anend cover 26.

A double valve body 27 has a pressure valve 28 and a waste valve 29, both seating at their upper ends, with a port 30 to the.

hydraulic operator and discharge port 31. A valve operating lever 32 is constructed as a drip guide with pins in loose holes at the lower ends'of valves 28 and 29 that allow enough angular movement to open either valve. The tension spring 33 draws the end of this valve lever 32 toward the valve body 27. At other end of the valve lever is loosely pivoted a compression pitman 34 which rests at its lower end in the bottom of a countersunk hole at the end of upper thermostat segment 20.

The water supply line to which connection is made is shown at 36 with a valve 37,- -a supply tube 38 and union connection 39.

to valve body 27. The valve body 27 is connected to the flue extension box with a. leg 40 and. to the upper head 41 of cylinder 42, the port 30 extending through these connction portions. The. cylinder 42 has a piston cup leather 43, an upper piston washer 44, and lower piston washer 45 and a nut at the upper end of a piston rod 46 to join these piston arts. 'The lower cylinder head 48 has a gui e49 for the piston rod 46 and this piston rod hasan inclined feather 50 hearing against'which is a roller 51 at the end of a bell crank 52. This bell crank 52 is pivoted at the lower end of a supporting bracket 53 and this bracket is attached at its lower end to the lower cylinder head 48 and at its upper end to the flue extension box 25. A compression link. 54 is pivoted at its lower end to one of the holes in the bell crank 52' and at upper end to one of the holes in a temperature setting lever 55. To the right hand end of lever 55 is attached tlhe pivoted nut 56 which has a compression aped bolt 57 attached, this bolt su porting the outer end of the thermostat. T e outer manually operated end of-lever 55 is linked to a weight 59 which is suflicient 'to balance the weight of the outer .end of the thermostat, also the downward thrust of pitman 34 occasioned by spring 33 and enough more to operate the valves without causing a damaging strain to the thermostat.

The flue temperature setting device is located and operable at two or more elevations. An upstairs indicator 60 is the same as the lower indicator 61 except the lower I one has its fastenings at top and carries a guide sheave 62, and hand levers 63 engaging with the different teeth of indicator 60 and 61 which have flue temperature notations opposite the teeth reading, say from 100 at the lowest tooth to 1200 at the highest tooth. The hand levers 63 are secured to a raisable and rotatable rod 64, so the levers 63 can be disengaged from teeth of 60 and 61 and set at some other temperature. Attached to this rod 64 is a collar 65 to which a'temper-ature operating chain 66 is attached, the chain passing over an ordinary sheave 67 and with a weight 68 at its lower end sufficient to keep the slack out of the chain; the connection from this weight 68 to weight 59 is made flexible so that no additional weight other than 59 can be put upon the thermostat.

At lower end of piston rod'46 is a swivel block 70 .upon which is pivoted a lever 71 which has a pivot at the right hand end to carry a lever 72 and has a chain 73 attached at other end for operating the check, 15. This chain 73 passes over ordinary sheaves 74'and 75 and is attached to the end of check lever arm 18 upon which is a weight 76. The weight 76- is sufiicient to balance the check 15 and approximately of theweight and friction of the piston and piston rod and lever 71, plus a sufiicient amount to insure certainty of operation when the waste valve 29 is o ened. The lever 72 has a damper chain 7 at its left side with a stop 7 ring 78 at its upper end which bears against the housing of a sheave 79. To this ring is attached a horizontal chain 80 which passes over a sheave-81 with a housing the same as that of sheave 79 and a stop ring 82 at its other end. To this ring is attached a chain 83 which is "connected to. damper 11 at its crank pin 14. Also attached to-this crank pin (or the lower end of the chain) is a damper weight 84. This weight produces a greater load on the piston than thecheck weight 76' so it drops until stop ring 78 bears on the housing of sheave 79 before the check weight 76 can start to drop, and it rises only when the check is closed and chain 73 can travel no'furtlien.

To the right hand end of lever 72 is atweight 88 is heavier on the piston than the damper weight 84. and can be raised only and 29 leak slightly, this leakage passing into the trough shaped valve lever 32 and this lever discharges into a funnel 90 at the upper end of a drip tube 91. The piston cup leather 43 leaks slightly and this leakage runs into a trough 92 which runs around lower cylinder head 48 and discharges through a pipe connection 93 into a T 94 that also receives drip tube 91 and discharges through a drip line 95 to the humidifier 8 or direct to the ash it 2.- The building structural parts are s own as a flooring 96 and floor joists 97 with wood cross pieces 98 attached to joists for supporting sheaves and lower indicator 61.

. The adjustment and operation of this controller are as follows :The thermostat may have a travel of from the lowest say 100 degrees to the highest permissible pressures say 1200 degrees and to prevent too sudden and wasteful extensive draft control changes, it is necessary to allow a temperature range say of 100 degrees throughout which the draft controls may be in any of the intermediate notched positions. This would require a vertical movement of the thermostat supporting member 57 of about The correct travel is obtained by marking the taper on feather 50 and the distance of the pivot centers in levers 52 and 55' such as will give the required amount. The range of travel of indicator rod 64 may be 4" from the 100 degree notch to the 1200 degree and if thermostat travel is then the pivots wouldbe set to give the ratio of 1 to 8. Different pivot holes are provided in lever 55 and bell crank 52 to permit different ratios. At one particular point in the vertical travel of pitman 34, both the pressure admitting valve 28 and the discharge valve 29 would be closed, and move ment above this point causes valvelever 32 to pivot on valve 28 and againstthe tension of spring 32 which would open water valve 29. A downward movement of pitman 34 would cause valve lever'32 to pivot on waste valve 29 and the supply pressure .bearing at the upper end of valve 28, which together with tension of spring 33 would c'ausethe supply valve 28 to. open.

The chain operating levers 71 and .72, the piston rod 46 and rod guide 49, also pivot block and pull chains 73, 77 and'85 are shown in Figs. 1, 2, 3, 4, 5. Fig. 2. shows the positions with check 15 open, damper 11 closed, and draft 7 closed :Figs.- 3 and 1 show check closed, damper closed,and draft closed; Fig. 4 shows check closed, damper open, and-draft closed; and Fig. 5 shows check closed, damper open and draft'open.

When the draft controls go through the range of shutting off the draft they operate in reverse order, as Fig. 5, then Fig.4, then Fig. 3, and completely off as Fig. 2. The piston travels approximately of passed over the ports.

weight chains73, 77 or 85 should break, the

controls go to shut off position. The regulator will raise the heat only when the parts are intact, and otherwise will go to safe position.

The novel construction shown can be ap plied in many forms; the hydraulic cylinder may be long enough for the three control travels and by using a continuous single chain and a pulley at each of the weights 76, 84, and 88, the operation will be the same as that shown. Inste'ad of using two separate valves, a ported piston valve can be Instead of using chains, the levers 71 and 72 may connect direct with one or more of the three draft controls.

side of the'flue extension so the thermostat Four or more pull chains may be. used by further increasing the number of rnace instead of the flue, or it may can be readily removed. A lever maybe placed at the lower end of the indicator rod 64 and the chain 66 moved by rotation of the handle 63, and rod 64 raised to rel'easeit from the locking notch.

I claim: I 1. The combination with av fuel burning device and its smoke flue, of a thermostat influenced by the temperature of-the products of combustion'in the device, a plurality of draft controls, and power means actuated bythe thermostat for operating the controls and a .water connection from the power mechanism to the humidifier.

4. Thecombination with a hot'air. heating furnace and its draft obstructingdevices, of

a thermostat, hydraulic power mechanism to oper'ate' .th e devices and controlled by the I thermostat, a humidifier in the heated air passage, and leakage waste connection from vices, a floating thermostat placed in the the mechanism to the humidifier.

5; The combination with a fuel burner and its draft'obstructin devices, of a thermostat influenced there y, an hydraulic ower mechanism to operate the devices an controlled by the thermostat, and a water connection from the mechanism to the ash pit of the burner.

6. The combination with a fuel burner, its draft obstructing devices and ash pit, of a thermostat influenced thereby, an hydraulic power mechanism controlled by the thermostat for operating said devices, a humidifier in the draft passage, a water connection from the mechanism to the humidifier, and

8. The com ination with a fuel burning device and its smoke flue, of a thermostat influenced by the temperature of the products of combustion in the device, a plurality of draft controls, power means actuated by the thermostat for operating the controls in sequence, the different controls including means for causin different loadings on the power means so that a lighter operated control will have its full travel before the heavier loaded control will start to move. 9. The combination with a fuel burner and three draft obstructing devices, a single driver therefor and an hydraulic regulator mechanism for operating the three devices from the driver each device coming to rest before the next is operated.

10. The combination with a fuel burner and three draft obstructing devices, of a single driver therefor, an hydraulic regulator for. operating the'three devices from the driver and comprising a lever pivoted to the driver with a connection at one end to one of the draft obstructing devices, and another lever pivoted. at the other end of the first mentioned lever with a connection at one end to the second obstructing device and at the other end of the third obstructing device. 11. The combination with a fuel burner and its draft obstructing devices, of an bydraulic power mechanism to operate the devices, a floating thermostat placed in the outgoing products of combustion, and a valve mechanism actuated by the thermostat to control the hydraulic power mechanism.

12. The combination with a fuel burner "and its draft obstructing devices, of an hydraulic power 111' to operate the de;

outgoing products of combustion, and a valve mechamsm comprising a plurality of valves with a variable point of reaction actuated by the stress of the themostat.

13. A construction in accordance with claim 12 including means for adjustably fixing the point of reaction of the sald valve mechanism.

14. A structure in accordance with claim 12 comprising means in connection with a valve mechanism for positioning the point of reaction-thereof in fixed relation to the movement of the hydraulic mechanism.

1'5. A structure in accordance with claim 12 comprising means for varying the oint of reaction, said means consisting of alever having two supports, one resting upon the movable hydraulic power mechanism, and the other adjustably set in a fixed position.

16. The combination with a fuel burner and a draft obstructing mechanism, of' a condition maintaining mechanism includin a thermostat that is affected by the heat 0 fuel burning, means for operating the condition maintaining mechanism in unison with the movement of the draft obstructing mechanism, and means for altering 'the set range of travel of the condition maintaining mechanism with relation to the obstructing mechanism.

17. The combination with a fuel burner and a draft obstructing mechanism, of a thermostatic mechanism affected by the heat of fuel burning, means for operating the mechanism in unison with the movement of the obstructing mechanism, means for setting and locking the range of travel of the mechanism with relation to the obstructing mechanism, said means comprising a rod adjustable and movable endwise having a plurality of operating mechanisms therefor;

18. The combination with a fuel burning device, of anair draft shutoff to the ash pit thereof, an air admitting check in'the smoke flue, and a 'damper'in the smoke flue between the check and the fuel burning chamb'er,wa thermostat located in the flue between the damper and the furnace, anhydraulic mechanism -to control the draft, a.

device and its draft controls, of a thermostat actuated b the heat from the burning fuel, an hydra ic motor for operatin the draft controls a valve controlled b stat which admits liquid to t e motor, and

controls so that they will operate separately in sequence to shut ofi draft and will operate t e thermomeans comprising weights for the draft in the reverse order to increase the draft each control coming to rest before the next one is operated.

20. The combination with a fuel burning device and its draft controls, of a thermostat actuated by the heat from burning fuel, an hydraulic motor for operating the draft controls, a valve controlled by the thermostat for admitting liquid to the motor, the draft controls being provided with weights for 10 operating them in sequence, and retrieving mechanism between the motor and the thermostat to keep their movements'in the same relative position.

WILLIAM L. MORRIS. 

